Suction device for internal combustion engine

ABSTRACT

The object of this invention is that a suction devise for an internal combustion engine is to be compact. 
     The suction devise comprising a casing having an air inlet and a plurality of outlets, a filter in the casing for filtering air from said air inlet, a collection chamber in the casing for receiving air from the filter, at least one throttle valve in the casing for controlling the flow of air from said filter to said collection chamber, and a plurality of suction pipes. 
     According to the present invention, the suction device can be made compact to thereby effectively use an engine room of an automobile.

This application is a divisional application of application Ser. No.08/307,461, filed Sep. 19, 1994, now U.S. Pat. No. 5,638,784 the subjectmatter of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field

The present invention relates to a suction device for supplying air andfuel to combustion chambers of an internal combustion engine, and moreparticularly to such a suction device which can be constructedcompactly.

2. Prior Art

In connection with a V-type internal combustion engine having aplurality of cylinders arranged in a V-shape, there is described aconventional suction device in U.S. Pat. Nos. 5,003,933 and 5,094,194,for example. In this conventional suction device, a plurality ofindividual suction pipes and a collector for distributing a suction airto the individual suction pipes are integrated compactly, but an aircleaner, a suction air quantity detecting means, a throttle valve, andfuel injection valves are not integrated. These latter elements areindividually mounted.

We described a problem to be solved by the invention.

It is an object of the present invention to provide a suction devicewhich can be constructed compactly so as to integrate all parts from anair cleaner to suction ports and eliminate any spaces other than an airpassage for supplying a suction air to an internal combustion engine,thereby widening spaces for mounting other parts and the internalcombustion engine in an engine room of an automobile or reducing a sizeof the engine room to effectively use the engine room.

The invention has below functions.

A casing of a suction device has such a shape as to be fitted with aspace defined between right and left banks of a V-type internalcombustion engine. The inside of the casing is partitioned into severalspaces for mounting an air cleaner, a collector, and a plurality ofindividual suction pipes in such a manner that these elements arearranged adjacent to each other.

The air cleaner, the collector, and the individual suction pipes arearranged adjacent to each other through a partition, thereby forming anair passage in each element. Accordingly, all parts constituting thesuction device can be integrated, and any unnecessary spaces other thanthe air passage can be eliminated to thereby realize a compact structureof the suction device.

SUMMARY OF THE INVENTION

In summary, the present invention provides a compact suction deviceincluding all parts from an air cleaner to suction ports.

The suction device has below functions. Air admitted from an inlet 5 ofan air cleaner 3 is introduced through a passage 6 and an air cleanerelement 33 to a suction air quantity detecting means 7. A throttle valve8 is located downstream of the suction air quantity detecting means 7.The air passed through the throttle valve 8 is introduced through acollector 10 to individual suction pipes 11 corresponding to cylindersof an engine. Thereafter, the air is sucked through suction ports 4 intocombustion chambers 12 of the engine. The passage 6, the individualsuction pipes 11, and the collector 10 are arranged adjacent to eachother through a partition or directly.

Further, a control unit 13 for controlling the engine is located in thepassage 6 downstream of the inlet 5 of the air cleaner 3.

According to the present invention, the suction device including the aircleaner to the suction ports can be made compact to thereby effectivelyuse an engine room.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional front view of a suction device according to afirst preferred embodiment of the present invention as mounted to aV-type internal combustion engine.

FIG. 2 is a schematic view of the suction device.

FIG. 3 is a sectional side view of a suction device according to asecond preferred embodiment of the present invention.

FIG. 4 is a sectional side view of a suction device according to a thirdpreferred embodiment of the present invention.

FIG. 5 is a view illustrating a flow of air in the suction deviceaccording to the first preferred embodiment.

FIG. 6 is a view illustrating a flow of air in the suction deviceaccording to the first preferred embodiment.

FIG. 7 is a view illustrating a flow of air in the suction deviceaccording to the first preferred embodiment.

FIG. 8 is a schematic side view illustrating a positional relationbetween the suction device and the internal combustion engine.

FIG. 9 is a schematic side view illustrating a control unit in thesuction device.

FIG. 10 is a sectional side view of a suction device according to afourth preferred embodiment of the present invention.

FIG. 11 is a schematic diagram illustrating an air passage shown in FIG.10.

FIG. 12 is a sectional side view of a suction device according to afifth preferred embodiment of the present invention.

FIG. 13 is a sectional side view of a suction device according to asixth preferred embodiment of the present invention.

FIG. 14 is a cross section taken along the line C--C in FIG. 13.

FIG. 15 is a sectional side view of a suction device according to aseventh preferred embodiment of the present invention.

FIG. 16 is a cross section taken along the line C--C in FIG. 15.

FIG. 17 is a schematic side view illustrating a swirl passage providedin a suction device according to an eighth preferred embodiment of thepresent invention.

FIG. 18 is a schematic plan view illustrating swirl control valvesprovided in the suction device according to the eighth preferredembodiment.

FIG. 19 is a schematic front view illustrating the swirl control valvesshown in FIG. 18.

FIG. 20 is an enlarged view of an essential part shown in FIG. 19.

FIG. 21 is an enlarged view of a modification of each swirl controlvalve in the eighth preferred embodiment.

FIG. 22 is a schematic perspective view illustrating a preferredembodiment of the swirl passage shown in FIG. 17.

FIG. 23 is a schematic perspective view illustrating another preferredembodiment of the swirl passage shown in FIG. 17.

FIG. 24 is a schematic perspective view illustrating the flows of airand fuel in forming a swirl.

FIG. 25 is a sectional front view of a suction device according to aninth preferred embodiment of the present invention.

FIG. 26 is a sectional side view of the suction device shown in FIG. 25.

FIG. 27 is a cross section taken along the line C--C in FIG. 26.

FIG. 28 is a view similar to FIG. 27, showing a tenth preferredembodiment of the present invention.

FIG. 29 is a top plan view illustrating a layout in an engine room of anautomobile.

FIG. 30 is a cross section taken along the line X--X in FIG. 29.

FIG. 31 is a sectional side view of a suction device according to aneleventh preferred embodiment of the present invention.

FIG. 32 is a sectional front view of a suction device according to atwelfth preferred embodiment of the present invention.

FIG. 33 is a sectional side view of a suction device according to athirteenth preferred embodiment of the present invention.

FIG. 34 is a cross section taken along the line B--B in FIG. 33.

FIG. 35 is a cross section taken along the line A--A in FIG. 33.

FIG. 36 is a schematic diagram illustrating a resonance suction lengthin the suction device shown in FIG. 33 when a variable induction valveis closed.

FIG. 37 is a diagram similar to FIG. 36, when the variable inductionvalve is opened.

FIG. 38 is a sectional side view of a suction device according to afourteenth preferred embodiment of the present invention.

FIG. 39 is a cross section taken along the line B--B in FIG. 38.

FIG. 40 is a cross section taken along the line A--A in FIG. 38.

FIG. 41 is a horizontal sectional view of a preferred embodiment of anair flow meter shown in FIG. 38.

FIG. 42 is a left side view of the air flow meter shown in FIG. 41.

FIG. 43 is a view similar to FIG. 41, showing another preferredembodiment of the air flow meter.

FIG. 44 is a schematic diagram illustrating a resonance suction lengthin the suction device shown in FIG. 38 when a variable induction valveis closed.

FIG. 45 is a diagram similar to FIG. 44, when the variable inductionvalve is opened.

FIG. 46 is a sectional side view of a suction device according to afifteenth preferred embodiment of the present invention.

FIG. 47 is a cross section taken along the line C--C in FIG. 46.

FIG. 48 is a cross section taken along the line A--A in FIG. 46.

FIG. 49 is a cross section taken along the line B--B in FIG. 46.

FIG. 50 is a sectional side view of a suction device according to asixteenth preferred embodiment of the present invention.

FIG. 51 is a cross section taken along the line B--B in FIG. 50.

FIG. 52 is a cross section taken along the line A--A in FIG. 50.

FIG. 53 is a sectional side view of a fuel gallery provided in a suctiondevice according to a seventeenth preferred embodiment of the presentinvention.

FIG. 54 is a sectional side view of the suction device including thefuel gallery shown in FIG. 53.

FIG. 55 is a sectional side view of a suction device according to aneighteenth preferred embodiment of the present invention.

FIG. 56 is a cross section taken along the line A--A in FIG. 55.

FIG. 57 is a top plan view illustrating a layout in an engine room of anautomobile when an engine is longitudinally mounted.

FIG. 58 is a view similar to FIG. 57, when the engine is transverselymounted.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first preferred embodiment of the present invention is shown in FIG.1, which is a sectional front view of right and left cylinder trains 1and 2 of an internal combustion engine 20 and a suction device 21. Theinternal combustion engine 20 is a V-type internal combustion enginewherein the right and left cylinder trains 1 and 2 are so arranged as toform a V-shape as viewed in front elevation. While the number ofcylinders in the V-type internal combustion engine 20 is six in thispreferred embodiment, it may be eight or twelve as known in the art. Thesuction device 21 including an air cleaner 3, suction ports 4, or theirpartial portions is located in a space defined between the right andleft cylinder trains 1 and 2.

Thus, the suction device 21 is designed to have a compact structure.FIG. 2a is a sectional front view of the suction device 21 with theright cylinder train 1 not shown, and FIG. 2b is a sectional side viewof the suction device 21. As shown in FIGS. 2A and 2B, air admitted froman inlet 5 of the air cleaner 3 is introduced through a passage 6 and anair cleaner element 33 to a suction air quantity detecting means 7. Thesuction air quantity detecting means 7 is an air flow meter of any typesuch as a hot-wire type, movable vane type, or Karman vortex type. Athrottle valve 8 is provided downstream of the suction air quantitydetecting means 7. The throttle valve 8 is electrically driven by amotor 9 in this preferred embodiment; however, it may be mechanicallydriven by a wire. The air passed through the throttle valve 8 isintroduced through a collector 10 into a plurality of individual suctionpipes 11 respectively communicating with a plurality of cylinders of theengine 20.

Thereafter, the air is sucked through the suction ports 4 intocombustion chambers 12 of the engine 20. In order to make the structurecompact, the passage 6 of the air cleaner 3, the individual suctionpipes 11, and the collector 10 are arranged in this order from the upperside in adjacent relationship to each other through partitions ordirectly. The order of arrangement of these sections is not limitative,but the passage 6 of the air cleaner 3, the collector 10, and theindividual suction pipes 11 may be arranged in this order from the upperside. A control unit 13 is located in the passage 6 of the air cleaner 3at a downstream portion thereof in consideration of compactibility andcoolability. With this arrangement, the control unit 13 can be cooled bythe air flowing in the passage 6. To ensure the compactibility, thecontrol unit 13 is located in the passage 6 just over the top of theindividual suction pipes 11 or the collecter 10. A plurality of fuelinjection valves 91 for injecting fuel are respectively located in thesuction ports 4 of the individual suction pipes 11, and a plurality ofair passages (swirl passages) 14 for forming a swirl of air in thecombustion chambers 12 are respectively located in the suction ports 4.

Further, a plurality of swirl control valves 15 for controlling thequantity of suction air flowing through the suction ports 4 and thequantity of suction air flowing through the air passages 14 arerespectively located in the individual suction pipes 11. In thispreferred embodiment, all or at least one of the individual suctionpipes 11, the swirl control valves 15, and the fuel injection valves 91are provided on the collecter 10 serving as a negative pressure chamberdownstream of the throttle valve 8. While the suction air quantitydetecting means 7 is located upstream of the throttle valve 8 in thispreferred embodiment, the detecting means 7 may be located downstream ofthe throttle valve 8. The throttle valve 8 is mounted to a member (aportion below the line A--A in FIG. 2B) forming the suction ports 4respectively communicating with suction ports 17 formed in the engine20.

A second preferred embodiment of the present invention is shown in FIG.3. In this preferred embodiment, the individual suction pipes 11 and thesuction ports 4 communicating with the suction ports 17 of the engine 20are formed in a single member (a portion below the line A--A in FIG. 3),and the throttle valve 8 is mounted to this member.

A third preferred embodiment of the present invention is shown in FIG.4. In this preferred embodiment, the collector 10 is formed just abovethe individual suction pipes 11. The air passed through the throttlevalve 8 is once raised to the collector 10 and then flows down into theindividual suction pipes 11. With this arrangement, the individualsuction pipes 11 are located nearer to the engine 20, so that thesuction device 21 can be easily mounted to the engine 20 with a simplestructure.

FIGS. 5, 6, and 7 illustrate the flow of suction air in the firstpreferred embodiment shown in FIG. 3. The air passage from the inlet 5of the air cleaner 3 to the collector 10 is formed so that the air flowsalong a certain plane A as shown in FIG. 6. On the other hand, the airpassage from the collector 10 to the suction ports 4 is formed so thatthe air flows along a certain plane B perpendicular to the plane A asshown in FIG. 6. Thus, the flow of suction air changes inthree-dimensional direction at the collector 10 only, thereby reducing asuction resistance.

FIG. 8 schematically illustrates a positional relation between theinternal combustion engine 20 and the suction device 21 as viewed inside elevation. Reference numerals 22 and 23 denote a front end and arear end of the engine 20, respectively. The air inlet 5 of the suctiondevice 21 is located just above the front end 22 of the engine 20.Accordingly, when the engine 20 is longitudinally mounted on anautomobile in such a manner that the front end 22 of the engine 20 isdirected to the front of the automobile, a cool air can be readilyintroduced from the air inlet 5 of the suction device 21. Further, apulley 24 and a fan belt 25 are provided at the front end 22 of theengine 20, so that there is no space for arranging the suction airquantity detecting means 7, the throttle valve 8, and a vertical passage26 (see FIG. 7) at the front end portion of the suction device 21.Accordingly, these elements are arranged at the rear end portion of thesuction device 21 just above the rear end 23 of the engine 20. In thesuction device 21, these elements are arranged behind the individualsuction pipes 11.

FIG. 9 schematically illustrates the arrangement of the control unit 13.As mentioned above, the control unit 13 is located downstream of the aircleaner element 33 in the air passage 6 of the air cleaner 3 in orderthat the control unit 13 can be cooled by a cool air just introducedfrom the air inlet 5. Further, in consideration of compactibility of thecollector 10 and the individual suction pipes 11 and maintainability ofthe control unit 13, the control unit 13 is located above a portion 29where the collector 10 and the individual suction pipes 11 are arranged.Since the control unit 13 must be adjusted upon delivery or inspectionafter manufactured, the control unit 13 is located at such a positionthat a lid (not shown) provided on the suction ports 4 can be removed ata portion upstream of a throttle valve mounting portion 30.

A fourth preferred embodiment of the present invention is shown in FIG.10. In this preferred embodiment, the air cleaner element 33 is locatedin a front portion of the air passage 6 of the air cleaner 3, and thesuction air quantity detecting means 7 is located in a rear passageportion 27 downstream of the air cleaner element 33. With thisarrangement, no bent passage portion is present upstream of the suctionair quantity detecting means 7, but a long straight passage portion canbe ensured upstream of the detecting means 7, thereby reducing adetection error of the detecting means 7. Further, the throttle valve 8is located in the vertical passage 26 for the purpose of prevention offixation of the valve 8 due to stain and for the purpose of improvementin maintainability.

FIG. 11 schematically illustrates the arrangement of the air passage inthe fourth preferred embodiment of FIG. 10. The air cleaner 3, thesuction air quantity detecting means 7, the throttle valve 8, and thecollector 10 leading to the individual suction pipes 11 having the fuelinjection valves 91 are arranged adjacent to each other. That is, asshown in FIG. 11, mounting members A, B, C, and D for respectivelymounting the above elements 3, 7, 8, and 10 are connected together in anintegral or direct fashion. With this arrangement, it is possible toreduce a detection error of the detecting means 7 due to suction airpulsation caused by blow-back from the combustion chambers upon fullopening of the throttle valve 8. That is, since the air passage from theair cleaner 3 to the collector 10 can be shortened, a volume of aircolumn in which vibration occurs can be reduced to thereby reduce thepulsation.

A fifth preferred embodiment of the present invention is shown in FIG.12. In this preferred embodiment, a circuit 32 of the suction airquantity detecting means 7 is located inside the control unit 13,thereby saving a space.

sixth preferred embodiment of the present invention is shown in FIGS. 13and 14. FIG. 14 is a cross section taken along the line C--C in FIG. 13.Referring to FIG. 14, reference numerals 11a, 11b, and 11c denoteindividual suction pipes extending along a left bank of an internalcombustion engine, and reference numerals 11d, 11e, and 11f denoteindividual suction pipes extending along a right bank of the internalcombustion engine. The individual suction pipes 11a, 11b, and 11c arearranged in a direction A, and the individual suction pipes 11d, 11e,and 11f are also arranged in the direction A. The throttle valve 8 lieson a line of symmetry between the arrangement of the individual suctionpipes 11a to 11c and the arrangement of the individual suction pipes 11dto 11f. Further, a throttle shaft of the throttle valve 8 extends in adirection B perpendicular to the direction A. This arrangement of thethrottle valve 8 is important because the throttle valve 8 is locatedadjacent to the collector 10. With this arrangement, the throttle valve8 is rotated to equally open to the left arrangement of the individualsuction pipes 11a to 11c and the right arrangement of the individualsuction pipes 11d to 11f, thereby effecting uniform distribution of airto the left and right arrangements.

A seventh preferred embodiment of the present invention is shown inFIGS. 15 and 16. FIG. 16 is a cross section taken along the line C--C inFIG. 15. In this preferred Embodiment, the throttle valve 8 is mountedin a vertical passage 34. As similar to the sixth preferred embodimentshown in FIGS. 13 and 14, the throttle shaft of the throttle valve 8extends in a direction B perpendicular to a direction A of arrangementof individual suction pipes 11a to 11c or arrangement of individualsuction pipes 11d to 11f. Accordingly, uniform distribution of air toboth arrangements can be effected.

An eighth preferred embodiment of the present invention is shown inFIGS. 17 to 24. FIG. 17 schematically shows a mechanism for forming aswirl of air in a combustion chamber 50 of an internal combustionengine. A suction port 46 as a downstream end portion of an individualsuction pipe 47 is arranged adjacent to a collector 45 downstream of athrottle valve (not shown) through a partition 51 in consideration ofspace saving. A suction passage (swirl passage) 49 is formed so as toconnect the collector 45 through the partition 51 to the suction port46. Further, a swirl control valve 48 is located in the individualsuction pipe 47 between the collector 45 and an outlet 52 of the suctionpassage 49. When a the swirl control valve 48 is closed, a suction airis allowed to flow through the suction passage 49, whereas when theswirl control valve 48 is opened, the suction air is allowed to flowthrough the individual suction pipe 47. With this arrangement, thesuction passage 49 can be easily formed because the collector 45 and theindividual suction pipe 47 are adjacent to each other through thepartition 51.

FIGS. 18 to 21 show a modified arrangement of plural swirl controlvalves 48 applied to a V-type internal combustion engine. As shown inFIGS. 18 to 20, a plurality of individual suction pipes 53 and 54 of theV-type internal combustion engine are alternately arranged so as tointersect each other at an intermediate portion in a space between rightand left banks of the engine. The swirl control valves 48 are located inthe individual suction pipes 53 and 54 at this intermediate portion, andare supported on a common shaft 55. If two or more support shafts forthe swirl control valves 48 were provided, an increased space wouldbecome necessary to cause an increase in cost. As shown in FIG. 21, eachswirl control valve 48 may be formed as a swirl control valve 100partially cut away as shown by a dashed line. Further, in the case whereeach suction port has two main passages, each swirl control valve may beformed as a swirl control valve partially cut away so as to close one ofthe two main passages.

FIG. 22 shows a preferred embodiment of the suction passage 49. In FIG.22, reference numerals 56a and 56b denote two suction valves provided ineach cylinder of an internal combustion engine, and reference numeral 57denotes a surface of connection between the individual suction pipes 47and an engine head. Two suction passages (swirl passages) 49a and 49bcommunicating the collector 45 to the suction port 46 are formed on anouter wall surface of each individual suction pipe 47. That is, thewalls of the suction passages 49a and 49b are partially formed by parts59a and 59b of the walls of the individual suction pipe 47. The suctionpassages 49a and 49b have respective outlets 52a and 52b opening towardthe suction valves 56a and 56b, respectively.

FIG. 23 shows another preferred embodiment of the suction passage 49. Inthis preferred embodiment, the outlets 52a and 52b of the suctionpassages 49a and 49b formed adjacent to each individual suction pipe 47open to the connection surface 57 independently of an outlet of thesuction port 46. The outlets 52a and 52b are respectively connected toinlets 61a and 61b of two suction passages (swirl passages) 63a and 63bformed in the engine head. Outlets 62a and 62b of the suction passages63a and 63b open near the suction valves 56a and 56b, respectively. Withthis arrangement, a strong swirl can be easily formed in the combustionchamber.

FIG. 24 shows the flows of air and fuel. Reference numerals 64a and 64bdenote the flows of air blown from the suction passages 49a and 49b,respectively, and reference numeral 65 denotes the sprays of fuelinjected from the fuel injection valve 91. The outlets 52a and 52b ofthe suction passages 49a and 49b are decided in direction so that theair flows 64a and 64b do not directly blow against the fuel sprays 65.If the air flows 64a and 64b having a high velocity blow directlyagainst the fuel sprays 65, the fuel sprays 65 change their directionsto strike against a wall surface of the suction passage in the enginehead, so that the fuel sprays 65 do not properly enter the cylinder ofthe internal combustion engine. To avoid this problem, the nozzles ofthe fuel injection valve 91 are decided in direction so that the fuelsprays 65 may be directed to central portions of the suction valves 56aand 56b, and the outlets 52a and 52b of the suction passages 49a and 49bare decided in direction so that the air flows 64a and 64b may bedirected to outside end portions of the suction valves 56a and 56b. Alsoin the case of a single suction valve per cylinder, a fuel spray from afuel injection valve is directed to a central portion of the suctionvalve, and an air flow from the suction passage 49 is directed to anouter peripheral portion of the suction valve.

A ninth preferred embodiment of the present invention is shown in FIGS.25 to 27. FIG. 27 is a cross section taken along the line C--C in FIG.26. In this preferred embodiment, a partition 70 is formed in thecollector 10 at a transversely central position thereof to define leftand right collectors 74a and 74b. Accordingly, the air passed throughthe throttle valve 8 is divided by the partition 70 to flow into theleft and right collectors 74a and 74b. Further, a variable inductionvalve 73 is mounted on the partition 70 so as to communicate the leftand right collectors 74a and 74b. The variable induction valve 73 isoperated according to an operational condition of the engine, therebychanging a substantial suction length of an individual suction pipe 71or 72. That is, when the variable induction valve 73 is closed in alow-speed condition of the engine, the substantial suction length can bemade large, whereas when the variable induction valve 73 is opened in ahigh-speed condition of the engine, the substantial suction length canbe made small.

A tenth preferred embodiment of the present invention is shown in FIG.28, which is a view similar to FIG. 27. In this preferred embodiment, apartition 75 separating the collector 10 into the left and rightcollectors 74a and 74b is extended rearwardly between two throttlevalves 77a and 77b to a downstream position of a suction air quantitydetecting means (not shown), which is located upstream of the throttlevalves 77a and 77b. Thus, an extended partition 76 is formed between thethrottle valves 77a and 77b and the suction ail quantity detectingmeans. That is, an air passage where the suction air quantity detectingmeans is located is formed as a single passage, but an air passage fromthe downstream of the detecting means through the throttle valves 77aand 77b to the collectors 74a and 74b is formed as dual separatepassages. The variable induction valve 73 mounted on the partition 75 inthis preferred embodiment is operated similarly to the ninth preferredembodiment shown in FIG. 27.

FIGS. 29 and 30 schematically illustrate a layout in an engine room 80of an automobile in which a suction device 81 according to the presentinvention is mounted. FIG. 30 is a cross section taken along the lineX--X in FIG. 29. The suction device 81 is located in a space definedbetween left and right banks and of a V-type internal combustion engine82. Reference numerals 83a and 83b denote spaces where an air cleaner, athrottle valve, etc. were conventionally located. In this preferredembodiment, since these elements are incorporated in the suction device81, any other parts located in the spaces 83a and 83b can be easilymaintained or inspected.

An eleventh preferred embodiment of the present invention is shown inFIG. 31. In this preferred embodiment, an EGR (exhaust gasrecirculation) passage 90 is provided in the suction device 21 so thatoutlets 93 of the EGR passage 90 respectively open into the individualsuction pipes at positions downstream of the fuel injection valves 91.If an EGR device is provided in a collector 90 as in the prior art, thefuel injection valves 91 located downstream of the collector 90 arestained by an EGR gas. To avoid this problem, the outlets 93 of the EGRpassage 90 in this preferred embodiment open downstream of the fuelinjection valves 91 to thereby prevent the stain of the valves 91 by theEGR gas.

A twelfth preferred embodiment of the present invention is shown in FIG.32. In this preferred embodiment, an EGR passage 95 is connected to aswirl passage 94 for forming a swirl of air in the combustion chamber ofthe internal combustion engine. With this arrangement, a suction airfrom the swirl passage 94 and an EGR gas from the EGR passage 95 can beuniformly mixed in the combustion chamber.

A thirteenth preferred embodiment of the present invention is shown inFIGS. 33 to 37. FIG. 34 is a cross section taken along the line B--B inFIG. 33, and FIG. 35 is a cross section taken along the line A--A inFIG. 33. A partition 105 for equally dividing an air passage in asuction device 100 into right and left areas is provided in a collector101, a throttle portion 102 in which the throttle valve 8 is located, avertical passage 103, and an upper horizontal passage 104. Further, avariable induction valve 106 is mounted on the partition 105 so as tocommunicate the right and left portions of the collector 101. In theupper horizontal passage 104, the partition 105 extends from the rearend of the passage 104 to the downstream of an air flow meter 107. Theair flow meter 107 is located in a single air passage, and an aircleaner element 108 is located upstream of the air flow meter 107 inthis single air passage. The purpose of provision of the partition 105is to obtain a supercharging effect. That is, when the variableinduction valve 106 is closed, the supercharging effect can be obtainedin a low-speed condition of an internal combustion engine, whereas whenthe variable induction valve 106 is opened, an effective point of thesupercharging effect is shifted to a high-speed region of operation ofthe engine.

This effect will be described in detail with reference to FIGS. 36 and37. In these drawings, reference numeral 110 denotes a cylinder of theinternal combustion engine, and reference numeral 109 denotes anindividual suction pipe of the suction device 100. FIG. 36 shows aclosed condition of the variable induction valve 106. In this closedcondition, a resonance suction length participating the supercharging isthe total length of the individual suction pipe 109, the collector 101,the throttle portion 102, the vertical passage 103, and the upperhorizontal passage 104, which length is a considerably large length.Accordingly, a resonance frequency is low, and a resonance effect occursin a low-speed condition of the engine. On the other hand, when thevariable induction valve 106 is opened as shown in FIG. 37, theresonance suction length becomes the length of the individual suctionpipe 109 plus the distance from it to the variable induction valve 106.Thus, the resonance suction length is shortened, and the resonanceeffect therefore occurs in a high-speed condition of the engine. In thismanner, the resonance suction length can be changed by opening andclosing the variable induction valve 106 to thereby obtain a resonancesupercharging effect in a wide operational region of the engine.

A fourteenth preferred embodiment of the present invention is shown inFIGS. 38 to 45. FIG. 39 is a cross section taken along the line B--B inFIG. 38, and FIG. 40 is a cross section taken along the line A--A inFIG. 38. This preferred embodiment is similar to the thirteenthpreferred embodiment with the exception that the partition 105 isextended to a position upstream of the air flow meter 107 and downstreamof the air cleaner element 108 in the upper horizontal passage 104.Accordingly, the air flow meter 107 is provided so as to pass throughthe partition 105 and extend across the upper horizontal passage 104.When the variable induction valve 106 is closed, the suction length canbe made larger than that in the thirteenth preferred embodiment shown inFIG. 33. A control unit 111 is located in the upper horizontal passage104, so as to be cooled by an air flow.

In this preferred embodiment, the air flow meter 107 is so designed asto measure the quantities of air flows in two air passages 121 and 122separated by the partition 105. FIGS. 41 and 42 show a preferredembodiment of the air flow meter 107. FIG. 42 is a cross section takenalong the line A--A in FIG. 41. As shown in FIGS. 41 and 42, lead wires118 are embedded in a probe 112, and two hot wires 113 and 114 areconnected to the lead wires 118. The two hot wires 113 and 114 arelocated in two air passages 116 and 117 respectively communicating withthe two air passages 121 and 122 separated by the partition 105.Accordingly, the velocities of air flows in the two air passages 121 and122 can be measured by the hot wires 113 and 114, respectively. Then, anaverage of the velocities thus measured is calculated to thereby detectthe quantity of suction air sucked into the internal combustion engine.Reference numeral 115 denotes a resistor for compensating a suction airtemperature. The resistor 115 is located in the air passage 117 in thispreferred embodiment; however, it may be located in the air passage 116.FIG. 43 is another preferred embodiment of the air flow meter 107. Inthis preferred embodiment, the air flow meter 107 has a common air inlet120 equally exposed to the two air passages 121 and 122 separated by thepartition 105, and has two air outlets 123 and 124 respectively openingto the two air passages 121 and 122. Further, a single hot wire 119 islocated in a common air passage formed just downstream of the air inlet120. With this arrangement, an average velocity of air flows in the twoair passages 121 and 122 can be measured by the hot wire 119. FIGS. 44and 45 schematically illustrate a resonance supercharging effect in thefourteenth preferred embodiment shown in FIG. 38. FIG. 44 shows a closedcondition of the variable induction valve 106. In this closed condition,the resonance suction length is a total distance from the individualsuction pipe 109 to the upstream of the air flow meter 107. Accordingly,the resonance suction length in this preferred embodiment can be madelarger than that in the thirteenth preferred embodiment shown in FIG.36, so that an engine speed at which the resonance supercharging effectoccurs can be shifted to a lower point as compared with the embodimentshown in FIG. 36. On the other hand, when the variable induction valve106 is opened as shown in FIG. 45, the resonance suction length isshortened as shown by a wavy line as similar to the embodiment shown inFIG. 37. Thus, an engine speed range where the resonance superchargingeffect occurs can be more widened as compared with the embodiment shownin FIGS. 36 and 37.

A fifteenth preferred embodiment of the present invention is shown inFIGS. 46 to 49. FIG. 47 is a cross section taken along the line C--C inFIG. 46; FIG. 48 is a cross section taken along the line A--A in FIG.46; and FIG. 49 is a cross section taken along the line B--B in FIG. 46.In this preferred embodiment, a part of the partition 105 is utilized asa substrate of a control unit 125. With this arrangement, it isunnecessary to define a special space for locating the control unit 125.The flow of suction air will be described with reference to FIGS. 47 to49. The suction air passes through the air cleaner element 108 and isthen divided by the partition 105 in the upper horizontal passage 104 asshown in FIG. 47. Then, the suction air flows down in the verticalpassage 103 and passes through the throttle portion 102 as shown in FIG.48. Then, the suction air enters the collector 101 and is led frominlets 126 of individual suction pipes to suction ports 127 of aninternal combustion engine as shown in FIG. 49.

A sixteenth preferred embodiment of the present invention is shown inFIGS. 50 to 52. FIG. 51 is a cross section taken along the line B--B inFIG. 50, and FIG. 52 is a cross section taken along the line A--A inFIG. 50. In this preferred embodiment, a part of the vertical partition105 is utilized as a substrate of the control unit 125 as similar to thefifteenth preferred embodiment shown in FIG. 46. Further, various wiringpatterns connected between the control unit 125 and various elementssuch as the air flow meter 107 and the throttle valves 8 are formed onthe vertical partition 105 and a horizontal partition 140. Morespecifically, a wiring pattern 137 connected to a power switch 130 foran igniter is printed on the horizontal partition 140 and the verticalpartition 105. Similarly, there are printed on the horizontal partition140 and/or the vertical partition 105 a wiring pattern 138 connected tothe air flow meter 107, a wiring pattern 136 connected to an actuator131 for driving the variable induction valve 106, a wiring pattern 139connected to a motor 132 for driving the throttle valves 8, and a wiringpattern 135 connected to the fuel injection valves 91. With thisarrangement, no wire harnesses are required to exhibit various effectssuch as weight reduction, cost reduction, and space saving. The flow ofsuction air in this preferred embodiment is similar to that in thefifteenth preferred embodiment shown in FIGS. 47 to 49.

A seventeenth preferred embodiment of the present invention is shown inFIGS. 53 and 54. In this preferred embodiment, a wiring 142 is built ina fuel gallery 141 connected to the fuel injection valves 91. The wiring142 is electrically connected to each fuel injection valve 91 totransmit a signal for controlling a valve opening timing and a valveopening period of each fuel injection valve 91. A power element 143 fordriving the fuel injection valves 91 and a fuel pressure regulator 144are mounted on the fuel gallery 141. While the power element 143 isheated, it is cooled by a fuel flowing in a fuel passage 145 formed inthe fuel gallery 141. The wiring 142 is connected to a terminal 146,which is in turn connected to a wiring pattern 147 leading to thecontrol unit 125 as shown in FIG. 54. With this arrangement, theconstruction of wiring to the fuel injection valves 91 can besimplified.

An eighteenth preferred embodiment of the present invention is shown inFIGS. 55 and 56. FIG. 56 is a cross section taken along the line A--A inFIG. 55. In this preferred embodiment, an EGR (exhaust gasrecirculation) device effective for purification of an exhaust gas isprovided. The exhaust gas from an exhaust pipe (not shown) is introducedfrom a passage 152 through a solenoid valve 151 to a passage 148. Asshown in FIG. 56, the passage 148 is formed in the vertical partition105, and communicate through branch pipes 150 respectively to individualsuction pipes 149. Accordingly, the exhaust gas is supplied from thepassage 148 through the branch pipes 150 and the individual suctionpipes 149 to cylinders of an internal combustion engine. The quantity ofthe exhaust gas to be supplied to the passage 148 is controlled by thesolenoid valve 151.

FIGS. 57 and 58 illustrate different layouts of a suction device 160according to the present invention in an engine room 165 of anautomobile 166. The layout shown in FIG. 57 is in the case where aV-type internal combustion engine is longitudinally mounted. In thiscase, since the suction device 160 is mounted between left and rightbanks 163 and 164 of the V-type internal combustion engine, side spacesbetween the engine and tires 167 can be widened, so that other parts canbe easily mounted in these spaces and the maintenance can be easilycarried out. On the other hand, the layout shown in FIG. 58 is in thecase where the V-type internal combustion engine is transverselymounted. In this case, since the suction device 160 is mounted betweenthe left and right banks 163 and 164 of the engine, a partition 169between the engine room 165 and a cabin 168 can be shifted frontward ofthe automobile 166. That is, the space of the engine room 165 can bereduced to thereby enlarge the space of the cabin 168. In this manner,various merits on the automobile 166 can be obtained owing to a compactdesign of the suction device 160.

According to the present invention, the suction device including the aircleaner to the suction ports is compact, so that the space of the engineroom can be effectively used in such a manner that a mounting space forother parts can be widened, the maintenance can be easily carried out,and a cabin space can be enlarged.

We claim:
 1. A suction device for an internal combustion engine,comprising:a casing having an air inlet and a plurality of outlets; afilter in the casing for filtering air from said air inlet; a collectionchamber in the casing for receiving air from the filter; at least onethrottle valve in the casing for controlling the flow of air from saidfilter to said collection chamber: a plurality of suction pipes each ofsaid suction pipes extending within the casing from the collectionchamber to a corresponding one of the plurality of outlets; and anexhaust recirculation passage communicating with said plurality ofsuction pipes.
 2. A suction device for an internal combustion engine,comprising:a casing having an air inlet and a plurality of outlets; afilter in the casing for filtering air from said air inlet; a collectionchamber in the casing for receiving air from the filter; at least onethrottle valve in the casing for controlling the flow of air from saidfilter to said collection chamber; a plurality of suction pipes each ofsaid suction pipes extending within the casing from the collectionchamber to a corresponding one of the plurality of outlets; a pluralityof swirl control valves in said plurality of suction pipes; and a commonshaft for driving said swirl control valves.
 3. A suction device for aninternal combustion engine, comprising:a casing having an air inlet anda plurality of outlets; a filter in the casing for filtering air fromsaid air inlet; a collection chamber in the casing for receiving airfrom the filter; at least one throttle valve in the casing forcontrolling the flow of air from said filter to said collection chamber;and a plurality of suction pipes each of said suction pipes extendingwithin the casing from the collection chamber to a corresponding one ofthe plurality of outlets, wherein a wall divides said collection chamberinto first and second regions, some of said suction pipes extending fromsaid first region and others of said suction pipes extending from saidsecond region; and there is a control valve in said wall for controllingair pressure between said first and second regions.
 4. A suction deviceaccording to claim 3, wherein said at least one throttle valve comprisesfirst and second throttle valves, said first throttle valvecommunicating with said first region and said second throttle valvecommunicating with said second region.
 5. A suction device for aninternal combution engine, comprising:a casing having an air inlet and aplurality of outlets; a collection chamber in the casing for receivingair from the air inlet; at least one throttle valve for controlling theair received by the collection chamber from said air inlet; a pluralityof suction pipes in the casing, each of said suction pipes extendingwithin the casing from the collection chamber to a corresponding one ofthe plurality of outlets;wherein: a wall divides said collection chamberinto first and second regions, some of said suction pipes extending fromsaid first region and others of said suction pipes extending from saidsecond region; and there is a control valve in said wall for controllingair pressure between said first and second regions.
 6. A suction deviceaccording to claim 5, wherein said at least one throttle valve comprisesfirst and second throttle valves, said first throttle valvecommunicating with said first region and said second throttle valvecommunicating with said second region.
 7. An engine assemblycomprising:an internal combution engine having a plurality of cylindersarranged in a V-shape; and a suction device, said suction devicehaving:a casing having an air inlet and a plurality of outlets; acollection chamber in the casing for receiving air from the air inlet;at least one throttle valve for controlling the air received by thecollection chamber from said air inlet; a plurality of suction pipes inthe casing, each of said suction pipes extending within the casing fromthe collection chamber to a corresponding one of the plurality ofoutlets;wherein: a wall divides said collection chamber into first andsecond regions, some of said suction pipes extending from said firstregion and others of said suction pipes extending from said secondregion; and there is a control valve in said wall for controlling airpressure between said first and second region; and wherein each of saidplurality of suction pipes is connected to a corresponding one of saidplurality of cylinders.
 8. A suction device for an internal combustionengine, comprising: a collection chamber for receiving air from an airinlet, a plurality of suction pipes, each suction pipe having an inletportion communicating with the collection chamber and an outlet portionfor connection to a respective cylinder of the engine, a plurality ofswirl ducts extending from said collection chamber to outlet portions ofrespective ones of said plurality of suction pipes, and a plurality ofswirl control valves in said suction pipes for controlling the relativeflow of air from said collection chamber to said outlet portions throughthe plurality of suction pipes and the plurality of swirl ducts, whereinthe suction pipes are arranged side-by-side and adjacent suction pipescross each other, the swirl control valves being provided in respectivecrossing portions of the suction pipes and being carried by a commonshaft by which they are controlled.
 9. A suction device according toclaim 1, wherein each swirl control valve is partially cut away.
 10. Asuction device according to claim 1, wherein the axial direction of thecommon shaft on which the swirl control valves are carried isperpendicular to the axial direction of the shaft of a throttle valvefor controlling the air flow through the collection chamber.
 11. Asuction device for an internal combustion engine, comprising:a casinghaving an air inlet and a plurality of outlets; a collection chamber inthe casing for receiving air from the air inlet; a plurality of suctionpipes in the casing, each of said suction pipes extending within thecasing from the collection chamber to a corresponding one of theplurality of outlets; a plurality of swirl ducts in the casing, theswirl ducts extending from said collection chamber to said plurality ofoutlets; a plurality of swirl control valves in said suction pipes forcontrolling the relative flows of air from said collection chamber tosaid plurality of outlets through the plurality of suction pipes and theplurality of swirl ducts; and a common shaft for driving said swirlcontrol valves.
 12. A suction device for an internal combustion engine,comprising:a casing having an air inlet and a plurality of outlets; afilter in the casing for filtering air from said air inlet; a collectionchamber in the casing for receiving air from the filter; at least onethrottle valve in the casing for controlling the flow of air from saidfilter to said collection chamber; a plurality of suction pipes, each ofsaid suction pipes extending within the casing from the collectionchamber to a corresponding one of the plurality of outlets; a pluralityof swirl control valves in said plurality of suction pipes; a commonshaft for driving said swirl control valves; and an exhaustrecirculation passage communicating with said plurality of suctionpipes.
 13. A suction device according to claim 12, wherein a walldivides said collection chamber into first and second regions, some ofsaid suction pipes extending front said first region and others of saidsuction pipes extending from said second region; andwherein a controlvalve is located in said wall for controlling air pressure between saidfirst and second regions.
 14. A suction device for an internalcombustion engine, comprising:a casing having an air inlet and aplurality of outlets; a filter unit containing a filter having an inletand outlet and being elongate from said inlet to said outlet of saidfilter unit; a collection chamber disposed in the casing for receivingair from the filter; a plurality of suction pipes, each of said suctionpipes extending within the casing from said collection chamber to arespective one of said plurality of outlets; and an air distributionunit including a connection path having at least one throttle valve forcontrolling an amount of said air and being formed by said plurality ofsuction pipes and said collection chamber, wherein said filter unit andsaid air distribution unit are associated by a common wall, and whereinwalls of said filter unit, said air distribution unit and saidconnection path are formed as the casing.
 15. A suction device accordingto claim 14, further comprising a plurality of swirl control valves insaid plurality of suction pipes and a common shaft for driving saidswirl control valves.